The present invention relates to connectors for terminating the end portion of sheathed heating elements and, more particularly, to a connector which serves to seal the end of the heating element and to mechanically and electrically connect an electric current carrying wire to the heating element.
Sheathed heating elements typically include a tubular sheath and a terminal pin which extends outwardly from the end of the sheath. The terminal pin is coaxially supported with respect to the sheath by a heat conductive, electrically insulative refractory-material. An electric current introduced to the terminal pin flows through a heating wire connected to the terminal pin to cause the wire to generate the desired heat.
For performance and safety reasons it is important that the terminal pin be electrically insulated from the sheath. This is accomplished during the manufacture of the heating element by coaxially locating the terminal pin with respect to the sheath to insure that a uniform thickness of the electrically insulative refractory-material surrounds the terminal pin. In this procedure, it is necessary to inspect the terminal pin-to-sheath dimension for each heating element to insure that there is at least a minimum acceptable thickness of insulating refractory-material separating the terminal pin and the sheath and that the insulative refractory material is of a uniform thickness. This inspection step contributes to the manufacturing costs of the heating element.